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In-Flight “Emergency”…

There’s no better way to test a pilot on his or her knowledge of emergency procedures than to simulate an in-flight unusual situation. I hesitate to use the word emergency here, because what most check pilots simulate is not really a full emergency. It’s more of a situation that requires the pilot’s attention, knowledge of procedures, judgement, and action.

Real Throttle Chops are a Thing of the Past

Gone (or almost gone) are the days when helicopter flight instructors or examiners did “throttle chops.” A throttle chop is a simulated engine failure in which the instructor or examiner twists the throttle to idle suddenly during flight. The engine and rotor RPM needles split and the rotor RPM needle immediately starts to drop. The student or pilot in command is required to immediately enter an autorotation. The experts estimate that the pilot has about two seconds to react properly. Failure to react could lead to unrecoverable low rotor RPM, which is a very bad thing.

Flight instructors and examiners pretty much stopped doing real throttle chops — the kind with absolutely no warning to the student — when helicopters started crashing. It seemed that in some cases, the student pilot or pilot in command wouldn’t react fast enough and the instructor or examiner didn’t either. Or, in some rare cases, the sudden reduction in power caused the engine to hiccup and really fail. Now most instructors usually warn the student in advance. Some slowly reduce the throttle, which leads to an audible change in engine sound that warns the student — not to mention that he or she can usually feel the adjustment in his or her collective hand. Others do a throttle chop and enter the autorotation at the same time, not even giving the student a chance to react.

Robinson Helicopter issued several safety notices recommending against throttle chops (see SN-27 and SN-38). The company even amended its Pilot Operating Handbook so practice autorotations would be done with just a tiny needle split rather than a full throttle-to-idle setting. (Not a very good simulation of an engine failure, if you ask me.)

So What’s an Instructor/Examiner to Do?

One of the instructor/examiners I’ve worked with in the past was extremely fond of failing instruments or illuminating warning lights. This particular instructor, who works for Robinson Helicopter, has a whole collection of circuit breaker tricks that he uses on unsuspecting students. He’ll pull an engine tach circuit breaker so the engine tachometer drops to 0 during flight. No lights, just that dead gauge. He does it to see how long before the pilot notices and whether the pilot knows what do do about it. He’ll do the same for other gauges that are important but not vital to safe flight.

I took my commercial check ride with this particular instructor/examiner and he made me do a run-on landing with “failed” engine tachometer, rotor tachometer, and governor (switch the governor off to simulate). The trick was to make very small collective inputs and hope the mechanical correlator would keep the RPM within range; listening to the sound of the engine helped a tiny bit. But I still managed to make that low rotor RPM horn go off as we approached the runway surface. Evidently, I exercised enough finesse, because although he was disappointed that the horn had come on, he didn’t fail me for it. Personally, I like to see him do it perfectly.

(A side note here. What real-life situation would require you to land with all that stuff inoperable? The only thing I can think of is a complete electrical failure. But even then, I think there’s some trick in the Robinson wiring scheme that keeps the tachs alive. Just can’t remember what it might be right now. Guess I need to look it up.)

My Recent Mechanical Failure

I’ve taken 6 check rides since I started flying about 8 years ago: 1 private, 1 commercial, and 4 Part 135s. There’s usually some kind of simulated failure during a flight. So when the Aux Fuel light came on during my most recent check ride on Thursday, my first inclination was to ask the examiner, “Did you do that?”

“What?”

We were doing an instrument approach at Williams Gateway Airport and I think he was paying more attention to my altimeter (I was supposed to be at 1880 feet) than anything else.

“That light,” I replied.

He saw the light. “No,” he said.

I didn’t believe him and asked him again. He repeated that he wasn’t responsible.

“Is the circuit breaker out?” I asked.

He looked down at the bank of circuit breakers at the base of his seat. “Yes.”

“Okay, it’s not a big deal,” I said. “It’s the auxiliary fuel pump. It’s a redundant system and we don’t need it for flight. The book says land as soon as practical. Do you want to push the circuit breaker back in?”

“No.”

(For the record, I would have.)

“Well, how about if we land here and have Kelly look at it?” I suggested. Kelly is my helicopter mechanic. By some unbelievable stroke of luck, we were landing at the airport where he was based and it wasn’t 5 PM yet.

He agreed that would be a good idea and talked to the tower for me. He then directed me to parking. I set it down in one of the helicopter parking spaces that Silver State uses. He pushed the circuit breaker back in. It popped back out. He got out to track down Kelly while I cooled down the engine and shut down.

Long story short: Kelly pulled off the side panel and found that one of the bolts on top of the fuel pump was loose. He removed the pump, bench tested it, tightened up the bolts, wrote up a logbook entry on a sticker for me, and sent us on our way. The whole process took a little more than an hour. The pump sounded much better when I primed the engine for startup and the light didn’t come on again as we did some more maneuvers at Williams Gateway and flew back to Scottsdale.

I passed the check ride. I like to think that the failed fuel pump helped me. It showed that I knew enough about the procedure to stay calm and make the right decision about it. In a way, it was a real-life “emergency” during the flight. Again, I don’t like to use the word emergency because there was never really any danger — unless, of course, the engine-driven fuel pump went bad, too. Then we’d have a problem.

Postscript

I flew back from Scottsdale with no further fuel pump problems.

The next day, I did a 50-minute scenic flight with two passengers on board. We were about 45 minutes into the flight — less than 5 miles from the airport — when the darn light came back on. I finished the tour — which was basically on the way to the airport anyway — and landed. When I pushed in the circuit breaker, it popped right out again.

When my passengers were on their way, I visited Ed, my local mechanic. I asked him to take a look at the pump when he had a chance, then put the helicopter away in my hangar, which is just down the row from his. He called with the bad news a while later. The pump was seized. I’d have to get a new one. I called the factory at 2:30 PM (their time) and managed to get it on a UPS truck for overnight (Saturday) delivery to Wickenburg. With luck, it’ll arrive as planned (Saturday deliver is a very iffy thing in Wickenburg) and Ed will put it in. I’ll be flying again on Sunday.

Unfortunately, it’ll take the flights I have scheduled on Sunday, Tuesday, and Thursday just to pay for the new pump.

3 thoughts on “In-Flight “Emergency”…”

About the wiring scheme that keeps the tachs alive: (quoting from 3-7 R22 POH)

“Tachometer Failure
If rotor or engine tach malfunctions in flight, use remaining tach to monitor RPM. If it is not clear which tach is malfunctioning or if both tachs malfunction, allow governor to control RPM and land as soon as practical.

Note
Each tach, the governor, and the low RPM warning horn are on separate circuits. Either the battery or the alternator can independently supply power to the tachs. A special circuit allows the battery to supply power to the tachs even if the master battery switch is off.”

disclaimers: a) this is from the R22 manual, so I am not sure it applies for the R44, I GUESS that it does, b) I am not trying to be a smartass; I was just perusing the POH earlier today, so it was not that hard to find that piece of information, and c) I know that this is a 4-year old post, but I thought it might be useful, for you or for other readers, to have the information together

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